Apparatus for firing furnaces



Jan 17, 1939. A. L. BAKER APPARATUS FOR FIRING FURNACES Filed Jan. 6, 1937 3 Sheets-Sheet l INVAENTOR ALBERT L. BAKER P- n. Wm

ATTORNEY Jan. 17, 1939. A. BAKER APPARATUS FOR FIRING FURNACES Filed Jan. '6, 1937 5 Sheets-Sheet 2 I I I I" INVENTOR ALBERT A. 84/19? ATTO R N EY A. L. BAKER 2,144,098

' APPARATUS FOR FIRING FURNACES Jan. 17, 1939.

Filed Jan. 6, 1937 5 Sheets-Sheet 3 ALBERT 1.. BAKER ATTORNEY Patented Jan. 17, 1939 UNITED STATES PATENT OFFICE APPARATUS FOR. FIRING FURNACES Application January 6, 1987, Serial No. 119,201 22 Claims. '(Cl.1581.5)

This invention relates to heating apparatus and refers in particular to means and apparatus for firing furnaces and improving the thermal efficiency thereof.

It is an object of my invention to improve the thermal efficiency of furnaces by providing means and apparatus for regulating and controlling the combustion of fuel in the furnace and the distribution of heat therein which is more flexible than existing apparatus and which provides proper combustion and uniform distribution of heat un: der all operating conditions of the furnace. To this end it is an object of my invention to provide an air register; a combination of air register and furnace; a combination of air register and burnor; and a combination of air register, burner and furnace; by means of which the quantity and direction of air supplied for the combustion of fuel, the intermingling of the fuel and air, and the distribution of flames and hot products of combustion within the furnace may be adjusted to maintain complete and rapid combustion of all fuel at a point near the fuel outlet of a burner and to provide uniform distribution of flame and hot products of combustion within a furnace for all operating conditions of the furnace. It is thus an object of my invention to provide an air register which is longitudinally adjustable along the axis of a furnace air port and which is provided with a plurality of rotatable vanes independently or simultaneously adjustable; and to provide in combination with such air register a burner, the fuel outlet portion of which is also longitudinally adjustable in position along such axis.

Other objects and advantages reside in the structure, arrangement and combination of parts which I will hereinafter describe in connection with a preferred embodiment of my invention, and with reference to the accompanying drawings in which like reference numerals are applied to like parts in the several figures, and in which:

Figure 1 is an elevational view,- partly in section, of a furnace, burner and air register constructed and assembled in accordance with my invention.

Figure'2 is an end view looking from the left hand side of Figure 1 but with the burner and furnace omitted.

Figure 3 is a vertical section showing the draft door plate and vane structure removed from the register assembly.

Figure 4 is a view of the register structure taken on line 4-4 of Figure 3.

Figure 5 shows a modified or alternative means for rotating the vanes.

Figure 6 is a half section taken on line 6--6 of Figure 5.

Figure 7 shows another alternative operating means for the vanes.

Figure 8 is a half section taken on line 88 of 5 Figure 7.

My invention contemplates the use of my air register with any furnace adapted to be heated by hot products of combustion and in which one or more openings or ports are provided in a wall, 10 or walls, of a combustion chamber of the furnace to supply air of combustion to the fuel outlet portions of one or more burners positioned within the furnace, but preferably the air register is employed in combination with a burner in which the 15 fuel outlet is located within the port itself and is adapted to eject a stream of hot products of combustion into the combustion chamber along a path substantially coincident with the axis of the port. By the term burner I refer to any apparatus adapted to eject fuel, such as gas and/or oil, in single or plural streams into the interior of the combustion chamber of a furnace, and by the terms fuel outlet or burner fuel outlet I refer to the nozzle or tip portion of such burner from which the fuel is ejected.

In order to more clearly point out the advantages of my invention I will refer to some of the factors influencing proper combustion and uniform distribution of heat in a furnace provided with burners and ports for supplying air of combustion to the burners before proceeding witha detailed description of the invention.

An insuflicient supply of air results in incomplete combustion of the fuel. Too great an air supply not only cools the hot gases but tends to blow the flame and hot gases toward the central portion of the furnace, and thus results in concentrated zones of heating within the furnace.

Too great a velocity of the air has a similar effect, whereas too low a velocitytends to cause a delayed intermingling of the air and fuel and insufficient distribution of the hot gases within the furnace. Rapid and complete intermingling of the air and fuel close to the burner fuel outlet is important because otherwise a long slow burning flame results and likewise causes concentrated zones of heating within the furnace. The rate of intermingling of air and fuel, the length of the flame, and the uniform distribution of hot gases within the furnace are also affected by the degree of turbulence in the air, fuel and hot gases at the burner fuel outlet. A highly turbulent condition at this point, and just beyond the burner fuel outlet, tends to promote the rapid intermingling of the air and fuel, and thus produces a short hot flame. Such condition also causes the hot gases to be rapidly and uniformly distributed to all parts of the furnace.

A long flame and delayed distribution of the hot gases caused by any of the above reasons is especially disadvantageous where burners are located on opposite furnace walls, such as in a box type furnace employed in the pyrolytic treatment of hydrocarbon products. In such furnaces the flames and hot gases from two burners opposed to each other meet in the central portion of the furnace with a resulting concentration of heat and turbulence at that point and a low degree of heating at points nearer the furnace walls. Such operation is clearly inefficient.

The position of the burner fuel outlet with respect to the longitudinal axis of the furnace port is another factor influencing proper combustion and an efficient utilization of heating area. If the fuel outlet is located within the combustion chamber itself or within the port but too close to the inner wall of the furnace, the air supplied for combustion will tend to form an envelope around the cone of flame and carry it towards the center of the furnace, thus causing a long flame and preventing a rapid distribution of the hot gases. If, on the other hand, the fuel outlet is located within the port but too close to the outer edge of the furnace wall, the flame will impinge directly upon the sides of the port with a resulting injury to the refractory lining of the port and an improper and inefficient distribution of the flame and gases.

It is thus evident that for proper furnace oper-' ation and maximum thermal efliciency it is desirable to maintain at all times and regardless of changes in the quantity of fuel being supplied to the burner: (1) a correct quantity and velocity of air for the amount of fuel consumption; (2) a highly turbulent condition in the air, fuel, and hot gases of combustion at and just beyond the burner outlet; and (3) the burner fuel outlet within the air port and at a proper distance from the inside edge of the furnace wall.

I accomplish such operation in my invention by providing the furnace with a burner having the fuel outlet portion thereof positioned within and adjustable along the longitudinal axis of the port and by directing the combustion air to such fuel outlet by means of an air register which has rotatable vanes for controlling the quantity and velocity of air admitted to the burner fuel outlet, as well as giving the air a swirling motion, and which is adjustable in position longitudinally or axially of the burner fuel outlet. As the quantity of fuel supplied to the burner is changed the position of the burner fuel outlet may be thus adjusted to maintain always the cone of flame so that it just clears the inside furnace wall at the edge of the port. The rotatable vanes are mounted on the furnace side of a draft door plate and are adapted to slide into the port opening and rotate on axes parallel to the longitudinal axis of the port. The draft door plate and vanes as a unit comprise the air register. By rotating the vanes and by longitudinally or axially adjusting the plate and vanes relative'to the outside wall of the furnace the amount of opening for admission of air to the port and burner may be closely regulated for any fuel consumption. The vanes impart a tangential or swirling motion to the air which creates the desired turbulent condition at a and just beyond the burner outlet. This condition may be augmented by arranging the ports in the burner fuel outlet to give the gas and/or oil escaping therefrom a tangential direction relative to the axis of flame projection and opposite in direction of rotation to that of the air stream. By adjusting the vanes longitudinally or axially relative to the burner outlet, the condition of maximum turbulance at the desired point can be maintained for any fuel consumption and burner outlet position.

Having thus shown the essentials of proper firing for maximum thermal efficiency and the general manner in which my invention accomplishes such firing, I will now describe in detail a preferred embodiment of my invention.

Referring to the drawings and more particularly to Figure l, the reference character I indicates the wall of a furnace which may be a furnace of any desired shape and structure and used for any desired purpose, such as a cracking furnace for hydrocarbon products, in which case the walls may be lined with tubes arranged inany desired manner. Such tubes may be arranged substantialy out of the path of hot products of combustion sweeping through the combustion chamber in which case they are heated predominantly by radiant heat, or they may be located'partially or wholly within the paths of such products. The wall I is provided with a port 2 adapted to receive a burner, such as an oil or gas burner or a combination of oil and gas, with the fuel outlet portion thereof located within the port. 3 designates a wind box attached to the furnace wall adjacent the port 2 and provided with an air duct 4. The wind box is provided with an opening 5 in alignment with the port 2 and an aligned opening 6 in the opposite wall. The numeral 1 designates a main frame plate for the register. This plate is provided with a central opening surrounded by a collar-like projection 8 adapted to fit within the port 2. Suitable packing 9, such as asbestos rope, may be placed between the member 8 and wall I. The plate I is attached to the furnace wall by any suitable means such as the anchor bolts I0 passing through the wall of the wind box and holes in plate 1. Studs l2 screw into tapped holes II in plate I and support a plate I3 in spaced relationship to plate I by means of collars l4 and nuts I 5. The plate I3 is provided with holes adapted to receive the studs l2. The plate I3 is also provided with an opening IS, a central opening I! surrounded by a collar-like projection 18, and a lower opening l9.

- A plate 20 is arranged over the opening 6 in the wind box wall and is secured to the wall by suitable means such as the bolts and nuts 2|. This plate is provided with an opening 22 aligning with the opening H5 in plate I3, a central opening 23 and a lower opening 24 aligning with the opening IS in plate l3. The openings I6 and 22 serve as peep holes into the interior of the furnace and as a means for inserting a torch to light the burner. A plate 25'is rotatably attached to the plate 20 by any suitable means such as screw 26 and is adapted to close the peep hole 22 when the same is not in use. If desired, a tube 27 may be inserted between the plates l3 and 20 at the openings I6 and 22.

Secured to the plate 20 by any suitable means such as the screws 28 is a bracket 29 having an end wall 30 adjacent the plate 20, an opposite end wall 3|, a top wall 32 and side walls 33. The walls 30 and 3| are provided with openings 30a and 31a, respectively,'aligning with the opening 24 in plate 20. Secured to the top wall 32 of the bracket by any suitable means such as the screws 34 is a slide plate 35 upon which brackets 36 are mounted and are adapted to slide. Brackets 36 are provided with suitable head rests v 37 adapted to support the burner and with wing screws 38 adapted to clamp the bracket against the slide plate 35. Resting upon head rests 37 and secured thereto by any suitable means such as the U bolt 39 and screws 40 is an elongated gas and/or oil burner 4|. As illustrated, the burner 4| comprises a combination gas burner 42 having a burner tip or fuel outlet 43 and an oil burner M having a burner tip or fuel outlet 45. The specific structure of the burner is no part of my invention, and either a gas burner or an oil burner could be used alone. If only a single burner is used it is evident that one of the brackets 36 may be omitted, if desired. A flanged collar 46 is adapted to slide over the elongated barrel portion of the burner 4| and close the opening 23 in plate 20. This collar is provided with suitable means such as a plurality of wing screws 41 for holding the flange portion of the collar tightly against the plate 20. A suitable ring gasket 48 is interposed between the flange on collar 46 and plate 20 while a suitable gasket 49 is interposed between said collarand thebarrel of the burner.

Mounted in the collar-like projection I8 of the plate H by any suitable means such as screw threads 50 is an elongated tubular member which extends through the opening in plate 1 and projects part way into the port 2. A diffusing ring 52a for the burner may be mounted upon the end of the member 5| if desired. The elongated barrel portion of the burner extends through the, tubular member 5| when the burner is in position. A draft door plate 52 provided with a central opening 53 is adapted to fit over said tubular member and slide upon the exterior surface thereof. If desired, one or more suitable bearings, such as the rollers 54 mounted on shafts 55, may be provided to assist in such sliding motion of the draft door plate.

As best shown in Figures. 3 and 4, the plate 52 is provided with a plurality of shafts 56 which are arranged in a circle having a circumference or perimeter less than the inside circumference or perimeter of the collar-like projection 8 on plate 1 and which have their axes at right angles to the plane of the plate. A vane 51 is secured to each of said shafts on the furnace side of the plate 52 by any suitable means such as wrapping the vanes partly around the shaft, as indicated at 51a, and spot welding. The shafts 56 extend through openings in the plate 52 which serve as bearings for the shafts, and a gear or pinion 58 is attached to each shaft on the opposite side of the plate from the vanes by suitable means such as a key. Shoulders 59 and nuts 59a secure the respective shafts and pinions on the plate 52 but permit rotation thereof. Surrounding said pinions and adapted to mesh with the teeth of each is an external ring gear 60 which is secured to the plate 52 by means of the studs 6| and nuts 62. The studs 6| project through slots 63 in the ring gear. The slots 63 are curved to permit a limited rotation of said gear about its axis relative to the plate 52 and are sufficiently long to permit the vanes to be rotated throughan angle of approximately 90 upon rotation of the ring gear.

Passing through a hole in the lower portion of the plate 52 and journalled therein is the reduced end 64a. of a shaft 64. A gear or pinion 65 is attached to the reduced portion of said shaft I upon the tubular member 5|.

bytany suitable means such as the key 66. This pinion is adapted to engage the teeth of the ring gear to cause rotation of the ring gear and a corresponding rotation of the vanes 51 by means of the pinions 58 and shafts56 when the shaft 64 is rotated about its axis. The reduced portion of the shaft provides a shoulder 68 which rests against the gear or pinion 65. A nut 61 and the shoulder 68 prevent longitudinal movement of the shaft 64 with respect to the plate 52but permit rotation of said shaft about its axis. Since the gears or pinions 58 and 65 rotate only through an angle of approximately 90 only a portion of the circumference of said gears need be provided with teeth, if desired.

As shownin Figure 1, the shaft 64 projects outwardly from the plate 52 through the openings 9, 241, 38a'and 3 la and is provided with a suitable means for rotating the same, such as handle 69, at the far end thereof. The portion of the shaft 64 which is contained within the bracket 29 is provided with a plurality of parallel teeth 1|] lying in planes at right angles to the axis of the shaft, and extending entirely around thecircumference of the shaft to provide a circular rack-like portion on that part of the shaft. A gear wheel 1| is adapted to mesh with the teeth of said rack and is attached to a shaft 12 journalled in the walls 33 of the bracket with its axis at right angles to the axis of the shaft 64. Suitable mechanism such as the handle 13 is provided for rotating the shaft 12 and gear II. It is thus evident that operation of handle 69 to rotate the shaft 64 causes a rotatable adjustment of the vanes 51 while operation of the handle 13 to rotate the gear wheel 1| causes a longitudinal movement of the shaft 64 and a corresponding sliding or longitudinal movement of the plate 52 and vanes 5'! Either handle 69 or handle 13 may be operated independently of the other to cause a separate and independent adjustment of either the rotational or longitudinal position of the vanes, or both handles may be operated simultaneously to cause both adjustments of the vanes simultaneously. Similarly handle 69 and/or 13 may be rotated simultaneously with the axial adjustment of the burner outlet. A wing screw 14 is threaded through an opening in the bracket wall 3| and engages the shaft 64 to serve as a locking means for both adjustments of the register. A draft scale 16 may be mounted on the bracket wall 3| to cooperate with a mark, or pointer 11, on shaft 64 and indicate the rotational position of the vanes 51. g

The draft door plate 52 is provided with a peep and torch hole opening 15 in alignment with openings I6 and 22. I

The operation of the hereinabove-described embodiment of my invention is as follows:

When the burner is shut down the handle 69 is operated to rotate the vanes 51 to their closed position, as shown in the upper half of Figure 4, and the handle 13 is operated to slide the draft door plate against the plate 1 to close the port opening. Either of these operations alone would substantially close the port, but it is desirable to do both to minimize the tendency of air to leak into the furnace and thereby to decrease the efficiency of other burners which may be operating. When it is desired to start up the burner, the shaft 64 is rotated to rotate the vanes to their fully openposltion, and the handle 13 is operated to slide the draft door plate back several inches from the furnace wall.. The burner is then ignited in the usual manner'by means of a torch which is passed through the openings 22, I6, and 15. The flame is adjusted for the desired fuel consumption in the usual manner and the axial position of the burner outlet within the port 2 is adjusted, by loosening the wing screw 38 and sliding the bracket 36 upon the plate 35, so that the cone of flame just clears the burner refractory tile at the furnace end of the port. The vanes 51 are then rotated by means of the shaft 64 to admit the proper quantity and velocity of air, and the vanes within the port are independently or simultaneously adjusted axially by means of the handle 13 to maintain a proper flame with maximum turbulence. For any substantial change in the fuel consumption during the operation of a burner it is evident that the burner outlet within the port must be readjusted axially to maintain the cone of flame in such position that it just clears the port wall at the furnace side of the same, and that the vanes must be correspondingly readjusted by shaft 64 to maintain proper combustion with maximum turbulence. In this manner the furnace and burner will always operate at a maximum degree of efficiency regardless of whether the burner is operating at maximum or some lower capacity. When the furnace has heated up it may be found necessary or desirable to slide the draft door and vanes farther away from the furnace and burner outlet, respectively, and for a properly designed burner operating at full capacity the vanes may be moved to the outer edge of the port opening. The damper on the forced draft fan may be used as an auxiliary control for the quantity and velocity of air supplied to the burner, but the major and final adjustment is made by means of the vanes. The vanes may be rotated slightly to compensate for any changes in the sizeof the air openings into the wind box caused by axial movement of the plate 52.

In Figures 5, 6, '7 and 8 I show alternative or modified means for rotating the shafts 56 and vanes 51 upon rotation of the shaft 64. In Figure'5 and Figure 6 cranks 58 and 65 have been substituted for the gears 58 and 55 respectively. Each of these cranks is provided with a pin 80 at the end thereof, and links 8| are provided to connect the respective successive pins. Thus a rotation of shaft 54 causes a rotation of crank 65, and this in turn causes a corresponding rotation of each of the cranks 58' and shafts 56.

The vanes 51 are attached to shafts 56 as in Fig-v ures 3 and 4. This arrangement eliminates any possibility of binding such as might occur between the ring gear and pinions shown in Figures 3 and 4, due to unequal expansion of parts when the register is used with preheated air.

In Figure 7 and Figure 8 the separate links 8| have been replaced by a continuous circular link 8|.

It is evident that various other equivalent means may be used to cause a rotation of the shafts 55 and vanes 51 upon rotation of the operating shaft 64. If desired, an internal ring gear may be used in place of the external gear shown in Figures 3 and 4. The ring gear 60 and pinions 58 and can be mounted on the furnace side of the plate 52 if desired.

I have illustrated my invention as used witha furnace provided with a wind box and forced draft but it is evident that it has the same utility when used with a furnace having natural draft, and no wind box or air ducts. When used without the wind box the plate 20 may be omitted and the bracket 29 and slide plate 35 supported by any suitable means such as the plate I3.

I prefer to employ a burner provided with an elongated barrel portion extending through the tubular member 5| and adjustable axially of the furnace port, as illustrated in the drawings, but my invention has the same utility with any desired type and shape of burner, the fuel outlet of which is axially adjustable with respect to the port. My air register may also be used with a burner and furnace in which the fuel outlet is not thus adjustable.

Although I prefer to use the shaft 64 to make both adjustments of the register, it is evident that separate members may be used to make the respective adjustments.

In the embodiment of my invention illustrated in the drawings and hereinabove described the vanes 51 are so arranged in the air register as to give air entering the port 2 and supplied to the burner fuel outlet a swirling motion in a counterclockwise direction of rotation. It is evident,

however, that the vanes and operating mechanism therefor may be arranged to give the air a swirling motion in the opposite, or clockwise, direction looking into the furnace, and my invention contemplates such an arrangement. Thus, burners on one side of the furnace may be provided with air registers adapted to rotate the air of combustion in a clockwise direction and those on the opposite side of the furnace may be provided with air registers adapted to rotate the air of combustion in the opposite or counterclockwise direction.

Many other modifications and variations of my invention may be made without departing from the spirit and scope thereof, and only such limitations should be imposed as are included in the appended claims. The specific embodiment and modifications disclosed in thespecification are for purpose of illustration and not limitation.

I claim:

1. In combination, a furnace having a port, an

air register provided with openings for the admission of air into said port and having a portion thereof adapted to fit within the port, means supporting said air register for longitudinal movement relative to the port, deflecting means for imparting a swirling motion to air admitted into the port arranged in said portion of the register which is adapted to ,fit within the port, means for changing the size of said air openings, and operating means for moving said register longitudinally of the port and for independently operating said means for changing the size of said air openings.

2. In combination, a furnace having a port, an air register having a portion thereof adapted to fit within said port, means supporting said air register for longitudinal movement relative to the port, a plurality of deflecting means for imparting a swirling motion to air admitted to said port arranged in the portion of the register which is adapted to fit within the port, means for controlling the amount of air admitted to the port by movement of said deflecting means, and operating means for moving the register longitudinally of the port and independently moving said deflecting means.

3. In combination, a burner provided with a fuel outlet, an air register provided with a plurality of rotatable vanes arranged to impart a swirling motion to air passing through said air register, means supporting said air register for longitudinal movement in the direction of the adjust the plate and vanes with respect thereto. 7

axis of said burner, and means for rotating said vanes and independently adjusting said register longitudinally relative to said burner fuel outlet.

4. In combination, a burner provided with an elongated barrel portion and a fuel outlet at one end thereof, an air register adapted to fit over said barrel portion, a plurality of rotatable vanes surrounding said barrel portion and mounted in said register for rotation about axes substantially parallel to the axis of the barrel portion of the burner, means for supporting said register for movement longitudinally of said barrel portion, and means for rotating said vanes and independently adjusting the register longitudinally rela tive to the burner fuel outlet.

5. In combination, a furnace having a burner port, a burner having a fuel outlet located within said port, an air register having a portion adapted to fit within said port, a plurality of rotatable vanes located in said portion of the register and arranged to impart a swirling motion to air supplied to said furnace around said fuel outlet, means forsupporting said burner fuel outlet and the vane portion of said register within the port, means for adjusting the burner fuel outlet longitudinally of the port, and means for adjusting said air register longitudinally of the port.

6. In combination, a furnace having a port, a burner having a fuel outlet located Within said port, means for supporting the burner with the fuel outlet within the port and adjustable longitudinally of the port, an air register including a plurality of pivotally mounted vanes, said vanes being arranged to impart a swirling motion to air supplied to said furnace around said fuel outlet, means for mounting said register for longitudinal movement relative to said port, and means for moving said vanes on their pivots and for adjusting the register longitudinally of the P rt.

7. In combination, a furnace having a port, a plate for closing said port, means for mounting said plate for longitudinal movement towards and away from the furnace and port, a plurality of vanes for imparting a swirling motion to air admitted to said port, means for mounting said vanes on the furnace side of said plate for rotation about axes which are substantially perpendicular to the plane of the plate and which are arranged on a perimeter sufficiently smaller than that of the port to permit the vanes to move within the port upon longitudinal movement of the plate, and means for rotating said vanes and independently moving said plate longitudinally of the port to axially adjust the plate and vanes with respect thereto.

8. In combination, a furnace having a burner port, a burner provided with a fuel outlet, means for mounting said burner with the fuel outlet within said port and adjustable longitudinally of the port, a draft door plate for the port, means for mounting said plate for independent longitudinal movement towards and away from the furnace and port, a plurality of vanes for imparting a swirling motion to air supplied to said furnace around said fuel outlet, means for mounting said vanes on the furnace side of said plate for rotation about axes which are substantially perpendicular to the plane of the plate and which are arranged on a perimeter sufiiciently smaller than that of the port to permit the vanes to move within the port upon longitudinal movement of the plate, operating means for rotating said vanes, and operating means for moving said plate longitudinally of said burner and port to axially 9. In combination, a furnace having a burner port, a burner provided with a fuel outlet, means for mounting said burner with the fuel outlet within said port and adjustable longitudinally of the port, a draft door plate for the port, means for mounting said plate for independent longitudinal movement towards and away from the furnace and portQa plurality of vanes to impart a swirling motion to air supplied to said furnace around said fuel outlet, means for mounting said vanes on the furnace side of said plate for rotation about axes which are substantially perpendicular to the plane of the plate'and which are arranged on a perimeter sufiiciently smaller than that of the port to permit the vanes to move within the port upon longitudinal movement of the plate, and means including a common operating member for rotating said vanes and for" 10. In combination, a furnace having a burner port, a burner provided with a fuel outlet, means for mounting said burner with the fuel outlet within said port and adjustable longitudinally of the port, a draft door plate for the port, means for mounting said plate for independent longitudinal movement towards and away from the furnace and port, a plurality of vanes to impart a swirling motion to air supplied to said furnace around said fuel outlet, means for mounting said vanes on the furnace side of said plate for rotation about axes which are substantially perpendicular to the plane of the plate and which are arranged on a perimeter sufficiently smaller than that of the port to permit the vanes 'to move within the port upon longitudinal movement of the plate, a shaft, means supporting said shaft for rotation about its axis and for longitudinal movement along its axis, said shaft having a plurality of parallel circumferential teeth lying in planes perpendicular to its axis 'for a portion of its length to provide a circular rack on the shaft, a gear wheel adapted to engage said rack teeth, means for supporting said gear wheel on an axis fixed with respect to the furnace and at right angles to the axis of the shaft, operating for a furnace, a supporting plate provided with an opening, a member projecting from the plane of said plate, a burner having an elongated portion adapted to fit Within said opening and provided with a fuel outlet at one end of said portion, means for supporting said burner with said,

elongated portion extending through said opening and with the fuel outlet portion thereof axially adjustable with respect to said plate, a draft door plate adapted to fit over the elongated portion of the burner and slidelupon said projecting member, a plurality of vanes, means for mounting said vanes on the side of said draft door plate adjacent the burner fuel outlet for rotation about axes substantially parallel to the axis of said elongated portion of the burner, and means for rotating said vanes and independently sliding said draft door plate on said projecting member to adjust the vanes relative to the burner fuel outlet.

12..In a combination air register and burner for a furnace, a supporting plate provided with an opening, a tubular member attached to said supporting plate adacent the opening therein and extending therefrom substantially perpendicular to the plane of the plate, a burner having an elongated portion adapted to fit within said opening and tubular member and provided with a fuel outlet at the end of said portion, means for supporting said burner with said elongated portion extending through the tubular member and with the fuel outlet adjacent the end of the tubular member distanct from said supporting plate and axially adjustable with respect thereto, a draft door plate provided with an opening adapted to fit over said tubular member and slide upon the exterior surface thereof, a plurality of vanes, means for mounting said vanes on the side of said draft door plate distant from the supporting plate for rotation about axes substantially perpendicular to the plane of the draft door plate, a shaft, means supporting said shaft for rotation about its axis and for longitudinal movement along its axis, said shaft having a plurality of parallel circumferential teeth lying in planes perpendicular to its axis for a portion of its length to provide a circular rack on the shaft, 9. gear wheel adapted to engage said rack teeth, means for supporting said gear wheel in fixed spaced relationship to said supporting plate and on an axis at right angles to the axis of the shaft,

1 operating means for rotating said shaft, operating means for rotating said gear wheel to cause longitudinal movement of the shaft, means for rotat- ,ing said vanes upon operation of said shaft by one of said operating means, and means whereby said draft door plate and vanes may be moved towards and away from said supporting plate upon operation of said shaft by the other of said operating means.

13. In an air register for a furnace, a supporting plate, a member projecting from the plane of said plate, a draft door plate slidably mounted upon said projecting member, a plurality of vanes for imparting a swirling motion to air passing through said register, and means for pivotally mounting said vanes on one face of said draft door plate for rotation about axes substantially perpendicular to the plane of the draft door plate.

14. In an air register for a furnace, a supporting plate, a member projecting from the plane of said plate, a draft door plate provided with means adapted to slide upon said projecting member, a plurality of vanes for imparting a swirling motion to air passing through said register, means for mounting said vanes on a side of said draft door plate for rotation about axes substantially perpendicular to the plane of the draft door plate, and means including a common operating member extending from said draft door plate for rotating said vanes and independently adjusting the draft door plate and vanes longitudinally of said projecting member.

15. In an air register for a furnace, a supporting plate, a member projecting from the plane of said plate, a draft door plate provided with means adapted to slide upon said projecting member; a plurality of vanes for imparting a swirling motion to air passing through said register, means for mounting said vanes on a side of said draft door-plate for rotation about axes substantially perpendicular to the plane. of the draftdoor plate, a shaft, means supporting said shaft for rotation about its axis and for longitudinal movement along its axis, said shaft having a plurality of parallel circumferential teeth lying in planes perpendicular to its axis for a portion of its length to provide a circular rack on the shaft, a gear wheel adapted to engage said rack teeth, means for supporting said gear wheel in fixed relationship to said supporting plate and on an axis at right angles to the axis of the shaft, operating means for rotating said shaft, operating means for rotating said gear wheel to cause longitudinal movement of the shaft, means for rotating said vanes upon operation of said shaft by one of said operating means, and means whereby said draft door plate and vanes may be moved towards and away from said supporting plate upon operation of said shaft by the other of said-operating means.

16. In an air register for a furnace, a supporting plate, a member projecting from the plane of said plate, a draft door plate provided with means adapted to slide upon said projecting member, a plurality of vanes for imparting a swirling motion to air passing through said register, means for mounting said vanes on a side of said draft door plate for rotation about axes substantially perpendicular to the plane of the draft door plate, a shaft attached to said draft door plate and. journalled thereon for rotation about its axis, said shaft extending from the plate and having a plurality of parallel circumferential teeth lying in planes perpendicular to the axis of the shaft for a portion of its length to provide a circular rack on the shaft, a gear wheel adapted to engage said rack teeth, means for supporting said gear wheel in fixed relationship to said supporting plate and on an axis at right angles to the axis of the shaft, means for rotating said vanes upon rotation of said shaft about its axis, means for rotating said shaft, and means for rotating said gear wheel to cause longitudinal movement of the shaft and thereby move the draft door plate and vanes towards and away from the supporting plate.

17. An air register of the character described adapted for use with a furnace, including a supporting plate, a member projecting from said supporting plate, a draft door plate slidably mounted on said projecting member, a plurality of vanes for imparting a swirling motion to the air passing through the register, means for pivotally mounting said vanes on a side of said draft door plate, and means including a common operating member for rotating said vanes and for independently adjusting said draft door plate ]and vanes'longitudinally of said projecting mem- 18. An apparatus of the character described, including, in combination a furnace having a port, an air register provided with openings for the admission of air into said furnace, means for mounting said air register for longitudinal movement with respect to said port, a plurality of vanes mounted on said air register for imparting a swirling motion to the air admitted into said furnace, means whereby said vanes may be moved to vary the size of said openings, and means whereby said air register may be moved longitudinally with respect to said port.

movement with respect to said port, a plurality of vanes mounted on said air register for imparting a swirling motion to the air admitted into said furnace, means whereby said vanes may be moved to vary the size of said openings, and means whereby said air register may be moved longitudinally with respect to said port, said last two mentioned means including a common operating member.

20. An apparatus of the character described, including, in combination, a furnace having a port, an air register provided with a plurality of,

pivotally mounted vanes adapted to extend into said port, said vanes being arranged to provide openings for the admission of air to said port, means for mounting said register for longitudinal movement relative to said port, and means for moving said vanes on their pivots and for independently adjusting the register longitudinally of said port.

21. An apparatus of the character described,

including a support, a member projecting vfrom said support, a plate member slidably mounted on said projecting member, a plurality of vanes, means for pivotally mounting said vanes on one side of said plate member and means for moving said vanes about their pivots and for independently adjusting said plate member and vanes longitudinally of said projecting member.

22. In combination, a furnace having a burner port, a burner having a fuel outlet located within said port, an air register having a portion extending into said port and including a plurality of pivotally mounted vanes, said vanes being arranged to impart a swirling motion to air supplied to said furnace around said fuel outlet, means for supporting said burner fuel outlet and the vanes of said air register within said port and means for adjusting said air register longitudinally of said port. 

